Input sensing device and a display device including the same

ABSTRACT

An input sensing device including: a power line; driving lines; a first signal line including sub-lines; a second signal line connected to the sub-lines; and sensor pixels connected to the power line, the driving lines, and the first signal line, wherein at least one sensor pixel of the sensor pixels includes: an optical sensor that transfers a photoelectrically converted charge from the power line to a first node in response to a driving signal provided through a first driving line of the driving lines; a first transistor connected between the first node and a first sub-line among the sub-lines, wherein the first transistor includes a gate electrode connected to the first driving line; and a second transistor connected between the first node and a second sub-line among the sub-lines, wherein the second transistor includes a gate electrode connected to the first driving line.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.17/189,965 filed on Mar. 2, 2021, which claims priority under 35 U.S.C.§ 119 to Korean Patent Application No. 10-2020-0046967 filed in theKorean Intellectual Property Office on Apr. 17, 2020, the disclosures ofwhich are incorporated by reference herein in their entireties.

1. Technical Field

An exemplary embodiment of the present invention relates to an inputsensing device and a display device including the same.

2. Description of the Related Art

Biometric authentication is form of security that measures and matchesbiometric features of a user to verify that a person trying to access aparticular device is authorized to do so. For example, in a displaydevice such as a smart phone or a tablet personal computer (PC), abiometric information authentication method using a user's fingerprintis widely used. To provide a fingerprint sensing function, a fingerprintsensor may be embedded in the display device or attached to and/or underthe display device. Such a fingerprint sensor integrated display deviceis called a fingerprint on display (FoD).

The FoD may include, for example, a light-sensing sensor. The FoD withthe light-sensing sensor may use a light emitting element provided in apixel as a light source and include an optical sensor array. The lightemitting element may be used to illuminate the user's finger. Theoptical sensor array may be implemented with, for example, a CMOS imagesensor (CIS), and may capture an image of the illuminated finger.

Detection capability of the input sensing device may deteriorate due tonoise coming from the outside the input sensing device (e.g.,fingerprint sensor). In other words, the sensitivity of the fingerprintsensor may be reduced by the noise.

SUMMARY

According to an exemplary embodiment of the present invention, there isprovided an input sensing device including: a power line; driving lines;a first signal line including sub-lines; a second signal line connectedto the sub-lines; and sensor pixels connected to the power line, thedriving lines, and the first signal line, wherein at least one sensorpixel of the sensor pixels includes: an optical sensor that transfers aphotoelectrically converted charge from the power line to a first nodein response to a driving signal provided through a first driving line ofthe driving lines; a first transistor connected between the first nodeand a first sub-line among the sub-lines, wherein the first transistorincludes a gate electrode connected to the first driving line; and asecond transistor connected between the first node and a second sub-lineamong the sub-lines, wherein the second transistor includes a gateelectrode connected to the first driving line.

The optical sensor may include: a photodiode connected between the powerline and the first node; and a transmission transistor connected betweenthe photodiode and the first node, wherein the transmission transistorincludes a gate electrode connected to the first driving line.

The sub-lines may extend in a first direction and may be arranged alongthe first direction, the second signal line may be arranged parallel tothe first signal line, and the driving lines may extend in a seconddirection crossing the first direction and be arranged along the firstdirection.

The second signal line may be connected to each of the first sub-lineand the second sub-line.

A width of the second signal line may be greater than a width of thefirst signal line.

The input sensing device may further include: a first driver connectedto the driving lines, wherein the first driver sequentially supplies thedriving signal to the driving lines; and a second driver connected tothe second signal line.

A sensor pixel farthest from the second driver among the sensor pixelsmay include an optical sensor and only one transistor directly connectedto the first signal line.

A sensor pixel closest to the second driver among the sensor pixels mayinclude an optical sensor and only one transistor directly connected tothe first signal line.

According to an exemplary embodiment of the present invention, there isprovided an input sensing device including: a power line; driving lines;a first signal line including a first sub-line, a second sub-line, and athird sub-line; a second signal line connected to the first signal line;and sensor pixel groups connected to the power line, the driving lines,and the first signal line, wherein at least one sensor pixel group amongthe sensor pixel groups includes: a first optical sensor fortransferring a photoelectrically converted charge from the power line tothe second sub-line in response to a driving signal provided through afirst driving line among the driving lines; a second optical sensor fortransferring a photoelectrically converted charge from the power line tothe second sub-line in response to a driving signal provided through asecond driving line among the driving lines; and a first transistorconnected between the first sub-line and the second sub-line, whereinthe first transistor includes a gate electrode connected to the firstdriving line.

The at least one sensor pixel group further includes: a secondtransistor connected between the third sub-line and the second sub-line,wherein the second transistor includes a gate electrode connected to thesecond driving line.

The first, second and third sub-lines may extend in a first directionand may be arranged along the first direction, the second signal linemay be arranged parallel to the first signal line, and the driving linesmay extend in a second direction crossing the first direction and bearranged along the first direction.

Each of the first and second optical sensors may include: a photodiodeconnected between the power line and the second sub-line; and atransmission transistor connected between the photodiode and the secondsub-line, wherein the transmission transistor includes a gate electrodeconnected to a corresponding driving line among the driving lines.

The second signal line may be directly connected to each of the firstsub-line and the third sub-line, and may not be directly connected tothe second sub-line.

The optical sensors may further include a third optical sensor, each ofthe first, second and third optical sensors may include: a photodiodeconnected between the power line and the second sub-line; and atransmission transistor connected between the photodiode and the secondsub-line, wherein the transmission transistor includes a gate electrodeconnected to a corresponding driving line among the driving lines.

The second driving line may be the same as the first driving line, andthe second driving line may be different from a driving line connectedto a gate electrode of a transmission transistor in each of the first,second and third optical sensors.

When a first driving signal having a gate-on voltage level is applied tothe first driving line, a second driving signal having a gate-on voltagelevel may be sequentially provided to the first, second and thirdoptical sensors.

According to an exemplary embodiment of the present invention, there isprovided a display device including: a display panel including pixelsfor displaying an image; and an input sensing panel disposed on thedisplay panel to sense light, wherein the input sensing panel includes:a power line; driving lines; a first signal line including sub-lines; asecond signal line connected to the sub-lines; and sensor pixelsconnected to the power line, the driving lines, and the first signalline, wherein a first sensor pixel among the sensor pixels includes: aphotodiode including a first electrode connected to the power line; atransmission transistor including a first electrode connected to asecond electrode of the photodiode, and a gate electrode connected to afirst driving line among the driving lines; and a first transistorincluding a first electrode connected to a first sub-line among thesub-lines, a second electrode connected to a second electrode of thetransmission transistor, and a gate electrode connected to the firstdriving line, and wherein a second sensor pixel among the sensor pixelsincludes: a photodiode including a first electrode connected to thepower line; a transmission transistor including a first electrodeconnected to a second electrode of the photodiode, and a gate electrodeconnected to a second driving line among the driving lines; and a secondtransistor including a first electrode connected to a second electrodeof the transmission transistor, a second electrode connected to a thirdsub-line among the sub-lines, and a gate electrode connected to thesecond driving line.

The sub-lines may extend in a first direction and may be arranged alongthe first direction, the second signal line may be arranged parallel tothe first signal line, and the driving lines may extend in a seconddirection crossing the first direction and may be arranged along thefirst direction.

A second electrode of the first transistor may be connected to the firstelectrode of the second transistor through a second sub-line among thesub-lines, and the second sub-line may be disposed between the firstsub-line and the third sub-line.

The second signal line may be directly connected to each of the firstsub-line and the third sub-line, and may not be directly connected tothe second sub-line.

According to an exemplary embodiment of the present invention, there isprovided an input sensing device including: a power line; a firstdriving line; a first signal line including a first sub-line and asecond sub-line; a second signal line connected to the first sub-lineand the second sub-line; an optical sensor connected between the powerline and a first node; a first transistor connected between the firstnode and the first sub-line; and a second transistor connected betweenthe first node and the second sub-line.

The first node may be directly connected to the first transistor and thesecond transistor.

A gate electrode of the first transistor may be connected to the firstdriving line and a gate electrode of the second transistor may beconnected to the first driving line.

The first sub-line may be electrically connected to the second sub-lineby the first transistor and the second transistor.

A width of the second signal line may be greater than a width of thefirst signal line.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a block diagram showing a display device according to anexemplary embodiment of the present invention.

FIG. 1B is a block diagram showing another exemplary embodiment of thedisplay device of FIG. 1A.

FIG. 2A is a cross-section view of the display device of FIG. 1A.

FIG. 2B is a cross-section view of the display device of FIG. 1A.

FIG. 3 is a block diagram showing an exemplary embodiment of an inputsensing device included in the display device of FIG. 1A.

FIG. 4 is a circuit diagram showing an exemplary embodiment of the inputsensing device of FIG. 3 .

FIG. 5 is a drawing showing an exemplary embodiment of a sensor pixelincluded in the input sensing device of FIG. 4 .

FIG. 6 is a waveform diagram describing an operation of the sensor pixelof FIG. 5 , according to an exemplary embodiment of the presentinvention.

FIG. 7 is a drawing describing a change in noise caused by the sensorpixels in FIG. 5 .

FIG. 8 is a circuit diagram showing another exemplary embodiment of theinput sensing device of FIG. 3 .

FIGS. 9A and 9B are circuit diagrams showing an exemplary embodiment ofa sensor array included in the input sensing device of FIG. 3 .

FIG. 10 is a block diagram showing another exemplary embodiment of aninput sensing device included in the display device of FIG. 1A.

FIG. 11 is a circuit diagram showing an exemplary embodiment of a sensorarray included in the input sensing device of FIG. 10 .

FIG. 12 is a waveform diagram describing an operation of the sensorarray of FIG. 11 , according to an exemplary embodiment of the presentinvention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Hereinafter, exemplary embodiments of the present invention will bedescribed in detail with reference to accompanying drawings. It is to beunderstood, however, that the described embodiments may be modified inmany different ways, and thus, should not limited to the embodimentsdescribed herein.

Throughout the specification, like reference numerals can refer to likeparts.

In addition, the size and thickness of elements in the accompanyingdrawings may be exaggerated for clarity of illustration.

FIG. 1A is a block diagram showing a display device according to anexemplary embodiment of the present invention. FIG. 1B is a blockdiagram showing another exemplary embodiment of the display device ofFIG. 1A. In FIGS. 1A and 1B, a display device is schematically shown.

Referring to FIGS. 1A and 1B, the display device 1000 may include adisplay panel 100 and a driver 200. For better understanding and ease ofdescription, the display panel 100 and the driver 200 are separatelyshown in FIGS. 1A and 1B, but the present invention is not limitedthereto. For example, all or a portion of the driver 200 may beintegrally implemented on the display panel 100.

All or at least a portion of the display panel 100 may have flexibility.

The display panel 100 includes a display area AA and a non-display areaNA. The non-display area NA may surround all or a portion of the displayarea AA. A pixel PXL (or a plurality of pixels) may be provided in thedisplay area AA, and the display area AA may be referred to as an activearea. The pixel PXL may include at least one light emitting element. Thedisplay device 1000 may drive the pixel PXL in response to image datainput from the outside, and may display an image in the display area AA.

In an exemplary embodiment of the present invention, the display area AAmay include an input sensing area FSA. At least some of the pixels PXLprovided in the display area AA may be included in the input sensingarea FSA.

In an exemplary embodiment of the present invention, as shown in FIG.1A, at least a portion of the display area AA may be set as the inputsensing area FSA.

FIG. 1A shows an exemplary embodiment in which only one input sensingarea FSA is set in the display area AA, but the present invention is notlimited thereto. For example, a plurality of input sensing areas FSAarranged regularly or irregularly may be set in the display area AA.Furthermore, the input sensing area FSA can be located anywhere in thedisplay area AA.

For example, FIG. 1A shows an exemplary embodiment in which the inputsensing area FSA is set in at least a portion of the display area AA,but the present invention is not limited thereto. For example, only atleast a portion of the input sensing area FSA may overlap at least aportion of the display area AA.

In another exemplary embodiment of the present invention, as shown inFIG. 1B, the entire display area AA may be set as the input sensing areaFSA. In this case, when performing an input sensing operation, the inputsensing operation may be performed only in a portion of the display areaAA that a user touches. Hereinafter, the input of a user may refer to apattern or biometric information formed by a ridge of the user's skin,and may include for example, the user's fingerprint or palm pattern.

The non-display area NA may be disposed around the display area AA, andmay be referred to as a non-active area. For example, the non-displayarea NA may include a line area, a pad area, and various dummy areas.

In an exemplary embodiment of the present invention, the display device1000 may further include a sensor pixel SPXL (or a plurality of sensorpixels) in the input sensing area FSA. The sensor pixel SPXL may becomposed of a sensor for sensing light. In an exemplary embodiment ofthe present invention, when light emitted from a light source (or pixelPXL) provided in the display device 1000 is reflected by the user's body(e.g., finger, palm, etc.), the sensor pixel SPXL may sense thereflected light and output a corresponding electrical signal (e.g. avoltage signal). The electrical signal may be transferred to the driver200 (e.g., an input detector 220) and may be used for input sensing.Hereinafter, the present invention will be described with reference toan exemplary embodiment in which the sensor pixel SPXL is used for inputsensing (e.g., fingerprint sensing). It is to be understood, however,that the sensor pixel SPXL may be used to perform various otherfunctions such as functions of a touch sensor, a scanner, and the like.

When the sensor pixel SPXL is provided in the input sensing area FSA (ordisposed on the input sensing area FSA), the sensor pixel SPXL mayoverlap the pixel PXL or be disposed around the pixel PXL. For example,some or all of the sensor pixels SPXL may overlap the pixel PXL, or thesensor pixel SPXL may be disposed between adjacent pixels PXL. Thesensor pixel SPXL and the pixel PXL may have the same or different size.The relative size and arrangement between the sensor pixel SPLX and thepixel PXL is not particularly limited.

When the sensor pixel SPXL is disposed adjacent to the pixel PXL oroverlaps at least a portion of the pixel PXL, the sensor pixel SPXL mayuse a light emitting element provided in the pixel PXL as a lightsource. In this case, the sensor pixel SPXL may be an input sensingsensor of a light sensing type together with a light emitting elementprovided in the pixel PXL. When an input sensing sensor embedded displaydevice (e.g., a fingerprint sensor embedded display device) isconfigured using the pixel PXL as a light source without a separateexternal light source, a thickness of the input sensing sensor of thelight sensing type and the display device including the same, may bereduced, and manufacturing cost thereof may be reduced.

In an exemplary embodiment of the present invention, the sensor pixelSPXL may be disposed on a different surface (e.g., a back surface)facing a surface (e.g., a front surface) on which an image is displayedamong both sides of the display panel 100. However, the presentinvention is not limited to thereto.

The driver 200 can drive the display panel 100. For example, the driver200 may output a data signal DS corresponding to image data to thedisplay panel 100. In addition, the driver 200 may output a drivingsignal for the sensor pixel SPXL, and may receive an electrical signal(e.g., a sensing signal SS) from the sensor pixel SPXL. The driver 200can detect the user's input (e.g., fingerprint, palm print, etc.) usingan electrical signal.

In exemplary embodiments of the present invention, the driver 200 mayinclude a panel driver 210 and an input detector 220. For betterunderstanding and ease of description, the panel driver 210 and theinput detector 220 are separately shown in FIGS. 1A and 1B, but thepresent invention is not limited thereto. For example, at least aportion of the input detector 220 may be integrated with the paneldriver 210 or may operate in conjunction with the panel driver 210.

The panel driver 210 may supply a data signal DS corresponding to theimage data to the pixel PXL while scanning the pixel PXL of the displayarea AA sequentially. In this case, the display panel 100 can display animage corresponding to the image data.

In an exemplary embodiment of the present invention, the panel driver210 may supply a driving signal for fingerprint sensing to the pixelPXL. Here, the driving signal may be provided to the pixel PXL so thatthe pixel PXL emits light and operates as a light source for the sensorpixel SPXL. In the present embodiment, the driving signal forfingerprint sensing may be provided to a pixel PXL (e.g., a pixel PXLlocated in the input sensing area FSA) located in a specific area in thedisplay panel 100.

In an exemplary embodiment of the present invention, the image datacorresponding to the input sensing area FSA may be provided orcontrolled by the input detector 220. For example, when performing theinput sensing operation, the input detector 220 may provide an imagedata corresponding to an image to be displayed in the input sensing areaFSA. In the alternative, when performing the input sensing operation,the input detector 220 may provide a control signal IPD to the paneldriver 210.

In addition, a driving signal for fingerprint sensing may be provided tothe sensor pixel SPXL by the input detector 220.

The input detector 220 may transfer a driving signal (e.g., a drivingvoltage) for driving the sensor pixel SPXL to the sensor pixel SPXL, andmay detect the user's input based on an electrical signal received fromthe sensor pixel SPXL. For example, the input detector 220 may detectthe user's fingerprint or palm print based on the sensing signal SSsupplied from the sensor pixel SPXL (or a sensor array including thesensor pixel SPXL).

The input detector 220 and sensor pixel SPXL (or sensor array) mayconstitute an input sensing device.

FIG. 2A is a cross-section view of the display device of FIG. 1A. Across-section in the input sensing area FSA of the display device 1000of FIGS. 1A and 1B is shown in FIG. 2A.

Referring to FIGS. 1A to 2A, the display device 1000 may include thedisplay panel 100 and a sensor array PS (or an input sensing panel)disposed on one surface of the display panel 100 in the input sensingarea FSA. In addition, the display device 1000 may include a substrateSUB, and a circuit element layer BPL, a light emitting element layerLDL, a first protective layer PTL1, a first adhesive layer ADL1, and awindow WIN disposed sequentially on one surface (e.g., an upper surface)of the substrate SUB. In addition, the display device 1000 may include asecond adhesive layer ADL2 and a second protective layer PTL2sequentially disposed on the other surface (e.g., a lower surface) ofthe substrate SUB. In other words, the circuit element layer BPL, thelight emitting element layer LDL, the first protective layer PTL1, thefirst adhesive layer ADL1, and the window WIN may be disposed on a firstsurface of the substrate SUB, and the second adhesive layer ADL2 and thesecond protective layer PTL2 may be disposed on a second surface of thesubstrate SUB. The first and second surfaces of the substrate SUB mayface each other.

The substrate SUB may be a base substrate of the display panel 100, andmay be a substantially transparent light-transmitting substrate. Thesubstrate SUB may be a rigid substrate including glass or temperedglass, or a flexible substrate including a plastic material. However,the material of the substrate SUB is not limited to thereto, and thesubstrate SUB may be made of various materials.

The circuit element layer BPL may be disposed on one surface of thesubstrate SUB, and may include at least one conductive layer. Forexample, the circuit element layer BPL may include a plurality ofcircuit elements constituting a pixel circuit of the pixel PXL, andlines for supplying various power and signals for driving the pixel PXL.In this case, the circuit element layer BPL may include a plurality ofconductive layers that constitute various circuit elements such as atleast one transistor, a capacitor, and the like and lines connectedthereto. In addition, the circuit element layer BPL may include at leastone insulation layer provided between a plurality of conductive layers.

The light emitting element layer LDL may be disposed on one surface ofthe circuit element layer BPL. The light emitting element layer LDL mayinclude a light emitting element LD (or a plurality of light emittingelements) connected to circuit elements and/or lines of the circuitelement layer BPL through a contact hole or the like. A plurality of thelight emitting elements LD may be spaced apart from each other on thesurface of the circuit element layer BPL. In an exemplary embodiment ofthe present invention, at least one light emitting element LD may beprovided in the pixel PXL (or pixel area PXA). For example, the lightemitting element LD may be composed of an organic light emittingelement, or an inorganic light emitting element such as a micro lightemitting diode (LED) or a quantum dot light emitting diode (LED). Inaddition, the light emitting element LD may be a light emitting elementmade of an organic material and an inorganic material in combination.

The pixel PXL may include circuit elements disposed in the circuitelement layer BPL and at least one light emitting element LD disposed inthe light emitting element layer LDL on the circuit element layer BPL.

The first protective layer PTL1 may be disposed on the light emittingelement layer LDL to cover the display area AA. The first protectivelayer PTL1 may include a sealing member such as a thin filmencapsulation (TFE) or an encapsulation substrate, and may furtherinclude a protective film in addition to the sealing member.

The first adhesive layer ADL1 may be disposed between the firstprotective layer PTL1 and the window WIN to bond the first protectivelayer PTL1 and the window WIN. The first adhesive layer ADL1 may includea transparent adhesive such as an optically clear adhesive (OCA) or anoptically clear resin (OCR), and may further include various adhesivematerials.

The window WIN may be a protective member disposed on a top of a moduleof the display device 1000 including the display panel 100, and may be asubstantially transparent light-transmitting substrate. The window WINmay have a multi-layer structure made up of a glass substrate, a plasticfilm, and/or a plastic substrate. The window WIN may include rigid orflexible materials, and the constituent material of the window WIN isnot particularly limited thereto.

The display device 1000 may further include a polarizer, ananti-reflection layer, and/or a touch sensor layer. For example, thedisplay device 1000 may further include a polarizer and/or a touchsensor layer disposed between the first protective layer PTL1 and thewindow WIN.

The second protective layer PTL2 may be disposed on the other surface ofthe substrate SUB. The second protective layer PTL2 may be bonded to thesubstrate SUB by the second adhesive layer ADL2.

The second adhesive layer ADL2 can firmly bond (or attach) the substrateSUB and the second protective layer PTL2. The second adhesive layer ADL2may include a transparent adhesive such as an optically clear adhesive(OCA). The second adhesive layer ADL2 may include a pressure sensitiveadhesive (PSA) in which an adhesive material acts when pressure isapplied to an adhesive surface thereof.

The second protective layer PTL2 may block an inflow of oxygen and/ormoisture from the outside, and may be provided in the form of a singlelayer or a multiple of layers. The second protective layer PTL2 may beformed of a film type to further secure flexibility of the display panel100. The second protective layer PTL2 may be bonded with the sensorarray PS through another adhesive layer, including a transparentadhesive such as the OCA.

A selective light blocking film may be further provided under the secondprotective layer PTL2. The selective light blocking film may block light(e.g., infrared light) of a specific frequency band among external lightincident on the display device 1000 to prevent the light from beingincident on the sensor pixel SPXL of the sensor array PS. The selectivelight blocking film may be provided under the second protective layerPTL2, but the present invention is not limited thereto.

The sensor array PS may be attached to the other surface (e.g., theback) of the display panel 100 through an adhesive or the like tooverlap at least one area of the display panel 100. For example, thesensor array PS may overlap the display panel 100 in the input sensingarea FSA. The sensor array PS may include the sensor pixels SPXL (or aplurality of sensor pixels) distributed with a predetermined resolutionand/or interval. For example, a plurality of the sensor pixels SPXL maybe spaced apart from each other in the sensor array PS.

In an exemplary embodiment of the present invention, an optical systemthat collects light directed to the sensor array PS and provides anoptical path may be provided on the sensor array PS. A width of alight-transmitting part guiding light in the optical system may bedetermined in consideration of sensing precision and light conversionefficiency. A condensing rate of light incident to the sensor array PSby the optical system can be improved. The optical system may be formedof an optical fiber, silicon, or the like.

The sensor pixel SPXL may have a number, size and arrangement so that afingerprint image can be obtained from an electrical signal output bythe sensor pixel SPXL. The sensor pixel SPXL and another sensor pixelSPXL can be densely set so that light reflected from a sensing object(e.g., a fingerprint, etc.) can be incident on the adjacent sensorpixels SPXL.

The sensor pixel SPXL can sense external light to output an electricalsignal, for example, a voltage signal corresponding thereto. Thereflected light incident on the sensor pixel SPXL may have a lightcharacteristic (e.g., a frequency, wavelength, size, etc.) due to avalley and a ridge formed in the user's body (e.g., finger). Therefore,the sensor pixel SPXL can output a sensing signal SS corresponding tothe light characteristic of the reflected light.

The sensing signal SS output from the sensor pixel SPXL may be convertedinto image data by the input detector 220, and may be used for useridentification (e.g., fingerprint authentication).

FIG. 2B is a cross-section view of the display device of FIG. 1A.

Referring to FIGS. 1A, 2A and 2B, the display device 1000 may furtherinclude a light blocking layer PHL including a pinhole PIH. The lightblocking layer PHL may be disposed inside the display panel 100, orbetween the display panel 100 and the sensor pixel SPXL, and may blocksome of the light incident on the sensor pixel SPXL. For example, someof the light incident on the light blocking layer PHL may be blocked,while other light incident on the light blocking layer PHL may passthrough a pinhole PH to reach the sensor pixel SPXL under the lightblocking layer PHL. For example, as shown in FIG. 2B, some of the lightincident on the light blocking layer PHL may pass through the pinhole PHto reach a plurality of sensor pixels SPXL. Other light incident on thelight blocking layer PHL may be reflected back towards the window WIN.

The pinhole PIH may refer to an optical hole, and may be a type oflight-transmitting hole. For example, the pinhole PIH may be alight-transmitting hole having the smallest size (or area) amonglight-transmitting holes formed by overlapping layers of the displaydevice 1000 on each other along a path through which the reflected lightpasses through the display panel 100 in a diagonal or vertical directionand enters the sensor pixel SPXL.

The pinhole PIH may have a predetermined width, for example, a width ofa range of 5 μm to 20 μm. Accordingly, as a distance from the lightblocking layer PHL increases (e.g., as it goes upward and downward fromthe light blocking layer PHL), a width of an optical opening area ineach layer of the display device 1000 may gradually increase.

The width (or diameter) of the pinhole PIH may be set to about 10 timesor more of a wavelength of the reflected light, for example, about 4 μmor 5 μm or more to prevent diffraction of light. In addition, the widthof the pinhole PIH may be set to a size sufficient to prevent an imageblur and to more clearly sense a shape of the fingerprint. For example,the width of the pinhole PIH may be set to about 15 μm or less. However,the present invention is not limited to thereto, and the width of thepinhole PIH may change depending on a wavelength band of the reflectedlight, a thickness of each layer of the module, or the like.

Only a reflected light passing through the pinhole PIH can reach thesensor pixel SPXL of the sensor array PS. Due to the very narrow pinholePIH, a phase of light reflected from the fingerprint and a phase of animage formed on the sensor array PS may have a difference of 180 degree.

The sensor pixel SPXL may output a sensing signal SS corresponding tothe reflected light passing through the pinhole PIH, for example, avoltage signal.

However, this is an example, and a configuration, a disposition, and adriving method of the sensor array PS for detecting the reflected lightfrom the fingerprint are not limited to the sensor array PS shown inFIGS. 2A or 2B.

FIG. 3 is a block diagram showing an exemplary embodiment of an inputsensing device included in the display device of FIG. 1A. The inputsensing device ISD may include a sensor array PS and an input detector220.

Referring to FIGS. 1A and 3 , the sensor array PS (or input sensingpanel) may include a sensor pixel SPXL. In an exemplary embodiment ofthe present invention, the sensor pixel SPXL may be arranged in atwo-dimensional array, but is not limited thereto. The sensor pixel SPXLmay include a photoelectric element that photoelectrically convertsincident light into a charge depending on an amount of the light.

The input detector 220 may include a horizontal driver 221 (e.g., afirst driver, or a scan driving circuit), a vertical driver 222 (e.g., asecond driver, or a lead-out circuit), and a controller 223.

The horizontal driver 221 may be connected to the sensor pixel SPXLthrough driving lines H1 to Hn (here, n is an integer of two or more).The horizontal driver 221 may be composed of a shift register or anaddress decoder, and may sequentially apply a driving signal (or drivingsignals) to the driving lines H1 to Hn. Here, the driving signal may bea signal for selectively driving the sensor pixel SPXL. For example, thehorizontal driver 221 may apply a driving signal in units of sensorpixel rows. For example, the driving signal may be provided to thesensor pixel row connected to the first driving line H1.

The sensor pixel SPXL selected and driven by the horizontal driver 221may sense light using a photoelectric element therein, and may output anelectrical signal (e.g., a sensing signal SS) corresponding to sensedlight, for example, a voltage signal. The electrical signal may be ananalog signal. In other words, the sensing signal SS may be an analogsignal.

The vertical driver 222 may be connected to output lines V1 to Vm (here,m is an integer of two or more), and may be connected to the sensorpixel SPXL through the output lines V1 to Vm. The vertical driver 222may process signals output from the sensor pixel SPXL.

For example, the vertical driver 222 may perform a correlated doublesampling (CDS) process for removing noise from an electrical signalprovided from the sensor pixel SPXL. In addition, the vertical driver222 may convert an electrical signal of an analog type into a signal ofa digital type. In an exemplary embodiment of the present invention, ananalog-digital converter may be provided for each sensor pixel column,and may process electrical signals (or analog signals) provided from thesensor pixel column in parallel.

The controller 223 may control the horizontal driver 221 and thevertical driver 222.

For example, the controller 223 may provide a first driving voltage(e.g., a gate-off voltage), a second driving voltage (e.g., a gate-onvoltage), a common voltage, a clock signal, and a control signal (e.g.,a start pulse) to the horizontal driver 221. In this case, thehorizontal driver 221 may generate a driving signal to selectively drivethe sensor pixel SPXL based on signals provided from the controller 223.

For example, the controller 223 may provide the clock signal and thecontrol signal to the vertical driver 222. In this case, the verticaldriver 222 may periodically sample the sensing signal SS provided fromthe sensor pixel SPXL based on the clock signal and the control signal,and may convert the sampled signal into a signal of a digital type.

In an exemplary embodiment of the present invention, the controller 223may generate image data corresponding to the sensing signal SS receivedfrom the vertical driver 222, and may process the generated image data.In addition, the controller 223 may detect an input (e.g., afingerprint, palm print, etc.) from the processed image data, and mayauthenticate the detected input or transfer the processed image data tothe outside.

However, this is merely an example, and the generation of image data andinput detection may be not performed by the controller 223. For example,image data generation and input detection may be performed by anexternal host processor or the like.

The horizontal driver 221, the vertical driver 222, and the controller223 are shown to be independently formed in FIG. 3 , but the presentinvention is not limited thereto. For example, the vertical driver 222and the controller 223 may be implemented as one integrated circuit, andthe horizontal driver 221 may be formed on the sensor array PS throughthe same process as the sensor pixel SPXL.

FIG. 4 is a circuit diagram showing an exemplary embodiment of the inputsensing device ISD of FIG. 3 . In FIG. 4 , the input sensing device ISDis briefly shown focused on a sensor pixel SPXL included in i−1-th toi+1-th sensor pixel rows (here i is a positive integer less than n) andj−1-th to j+1-th sensor pixel columns (here j is a positive integer lessthan m), and the vertical driver 222 (or integral circuits) connectedthereto. FIG. 5 is a drawing showing an exemplary embodiment of a sensorpixel SPXL included in the input sensing device ISD of FIG. 4 . FIG. 5shows the sensor pixel SPXL included in the i-th sensor pixel row andthe j-th sensor pixel column.

Referring to FIGS. 3 to 5 , the input sensing device ISD (or sensorarray PS) may include driving lines Hi−1, Hi, and Hi+1, output linesVj−1, Vj, and Vj+1 (or second signal lines), signal lines RXj−1, RXj,and RXj+1 (or first signal lines), a power line PL1, and sensor pixelsSPXL connected thereto.

The driving lines Hi−1, Hi, and Hi+1 may extend in a second directionDR2, and may be arranged in a first direction DR1 crossing the seconddirection DR2.

The output lines Vj−1, Vj, and Vj+1 may extend in the first directionDR1, and may be arranged in the second direction DR2.

The signal lines RXj−1, RXj, and RXj+1 may extend in the first directionDR1, and may be arranged in the second direction DR2. The signal linesRXj−1, RXj, and RXj+1 may extend parallel to the output lines Vj−1, Vj,and Vj+1, and the signal lines RXj−1, RXj, and RXj+1 and the outputlines Vj−1, Vj, and Vj+1 may be alternately arranged in the seconddirection DR2.

In exemplary embodiments of the present invention, each of the signallines RXj−1, RXj, and RXj+1 may include a plurality of sub-lines. Asshown in FIG. 5 , the j-th signal line RXj may include a first sub-lineRX_S1 and a second sub-line RX_S2. The first sub-line RX_S1 and thesecond sub-line RX_S2 may extend in the first direction DR1, and may bearranged in the first direction DR1. The first sub-line RX_S1 may beseparated from the second sub-line RX_S2. For example, a pair oftransistors may be disposed between the first sub-line RX_S1 and thesecond sub-line RX_S2.

The power line PL1 may be arranged in a matrix form, and a commonvoltage VCOM (e.g., a ground voltage) may be applied to the power linePL1.

The sensor pixels SPXL may be connected to the driving lines Hi−1, Hi,and Hi+1, the output lines Vj−1, Vj, and Vj+1 (second signal lines), thesignal lines RXj−1, RXj, and RXj+1 (or first signal lines), and thepower line PL1.

Since the sensor pixels SPXL are substantially equivalent to each other,the sensor pixel SPXL included in the i-th sensor pixel row and j-thsensor pixel column will be described as representative of the sensorpixels SPXL.

Referring to FIG. 5 , the sensor pixel SPXL may include an opticalsensor PSC, a first transistor T1, and a second transistor T2.

The optical sensor PSC may be connected to the power line PL1, the i-thdriving line Hi, and a first node N1, and may transfer aphotoelectrically converted charge (or sensing signal SS, see FIG. 1A)to the first node N1 in response to a driving signal provided throughthe i-th driving line Hi.

In an exemplary embodiment of the present invention, the optical sensorPSC may include a photodiode PD and a transmission transistor T_TX.

The photodiode PD may be electrically connected between the power linePL1 and the first node N1, and may generate a charge (or a current)based on the incident light. In other words, the photodiode PD canperform a function of photoelectric conversion. For example, an anode ofthe photodiode PD may be connected to the power line PL1, and a cathodeof the photodiode PD may be electrically connected to the first node N1.In other words, a first terminal of the photodiode PD may be connectedto the power line PL1, and a second terminal of the photodiode PD may beelectrically connected to the first node N1.

The transmission transistor T_TX may include a first electrode (or firsttransistor electrode) connected to the cathode of the photodiode PD, asecond electrode (or second transistor electrode) electrically connectedto the first node N1, and a gate electrode connected to the i-th drivingline Hi.

In other words, the transmission transistor T_TX may be electricallyconnected between the cathode of the photodiode PD and the first nodeN1. In this case, the transmission transistor T_TX may be turned on inresponse to a driving signal (e.g., a driving signal at a gate-onvoltage level that turns on a transistor) provided through the i-thdriving line Hi, and may transfer the photoelectrically converted chargefrom the photodiode PD to the first node N1.

In FIG. 5 , the optical sensor PSC is shown to include the photodiode PDand the transmission transistor T_TX, but the optical sensor PSC is notlimited thereto. For example, the optical sensor PSC may further includea transistor for initializing the photodiode PD, a capacitor fortemporarily storing a charge of the photodiode PD, and a transistor fortransferring a predetermined signal (e.g., a current), instead of thecharge of the photodiode PD, to the first node N1 in response to thecharge of the photodiode PD.

The first transistor T1 may include a first electrode connected to thefirst sub-line RX_S1, a second electrode connected to the first node N1,and a gate electrode connected to the i-th driving line Hi. In otherwords, the first transistor T1 may be connected between the firstsub-line RX_S1 and the first node N1. In this case, the first transistorT1 may be turned on in response to a driving signal (e.g., a drivingsignal at a gate-on voltage level) provided through the i-th drivingline Hi, and may electrically connect the first node N1 and the firstsub-line RX_S1.

The second transistor T2 may include a first electrode connected to thefirst node N1, a second electrode connected to the second sub-lineRX_S2, and a gate electrode connected to the i-th driving line Hi. Inother words, the second transistor T2 may be connected between thesecond sub-line RX_S2 and the first node N1. In this case, the secondtransistor T2 may be turned on in response to a driving signal (e.g., adriving signal at the gate-on voltage level) provided through the i-thdriving line Hi, and may electrically connect the first node N1 and thesecond sub-line RX_S2. When the first and second transistors T1 and T2are turned on, the first and second sub-lines RX_S1 and RX_S2 may beelectrically connected to each other.

The j-th output line Vj may be connected to each of the first sub-lineRX_S1 and the second sub-line RX_S2. In this case, the first electrodeof the first transistor T1 may be electrically connected to the j-thoutput line Vj through the first sub-line RX_S1, and the secondelectrode of the second transistor T2 may be electrically connected tothe j-th output line Vj through the second sub-line RX_S2. Here, thefirst transistor T1 and the second transistor T2 may form a current pathbetween the first node N1 and the j-th output line Vj in response to adriving signal provided through the i-th driving line Hi.

When a driving signal is not applied to the i-th driving line Hi (orwhen a driving signal at a gate-off voltage level that turns off atransistor is applied to the i-th driving line Hi), the first transistorT1 and the second transistor T2 may maintain a turn-off state, and mayelectrically separate the optical sensor PSC from the j-th signal lineRXj (e.g., first sub-line RX_S1 and second sub-line RX_S2). In addition,since the driving signal is not applied to the i-th driving line Hi, thefirst sub-line RX_S1 and the second sub-line RX_S2 may be electricallyseparated from each other, and the possibility that noise flows throughthe j-th signal line RXj and a size of the noise may be reduced. Forexample, since the first sub-line RX_S1 and the second sub-line RX_S2are electrically separated, the length of the wiring for the j-th signalline RXj is decreased, thereby reducing the amount of noise.

In addition, the first transistor T1 and the second transistor T2 mayblock a leakage current flowing through the transmission transistorT_TX, and may block noise caused by a leakage current of the sensorpixel SPXL that is not selected.

In other words, the first transistor T1 and the second transistor T2 canconstitute a noise prevention circuit for each sensor pixel SPXL.

In exemplary embodiments of the present invention, a load (or aresistance value) of the j-th output line Vj may be smaller than a loadof the j-th signal line RXj. For example, a first line width W1 of thej-th output line Vj may be greater than a second line width W2 of thej-th signal line RXj (e.g., second sub-line RX_S2). The noise may beblocked through the j-th signal line RXj with a relatively large load,and a charge (e.g., a sensing signal with reduced noise) may be directlyprovided to the vertical driver 222 through the j-th output line Vj witha relatively small load. In an alternative embodiment, the first linewidth W1 and the second line width W2 may be the same as each other orthe second line width W2 may be greater than the first line width W1.

In FIG. 5 , the transmission and first and second transistors T_TX, T1,and T2 are shown to P-type transistors, but at least some of thetransmission and first and second transistors T_TX, T1, and T2 may beN-type transistors, so that a circuit structure of the sensor pixel SPXLmay be variously modified.

Referring back to FIG. 4 , the vertical driver 222 may include integralcircuits.

The integral circuits may be connected to the output lines Vj−1, Vj, andVj+1 through input terminals OTj−1, OTj, and OTj+1, respectively, andmay generate output signals VOUTj−1, VOUTj, and VOUTj+1, respectively.Since the integral circuits are substantially equivalent to each other,an integral circuit connected to the j-th output line Vj will bedescribed as representative of the integral circuits.

The integral circuit (or vertical driver 222) may include an amplifierAMP, a capacitor CF, and a switch SW. A first input terminal (e.g., aninput terminal of a positive polarity (+)) of the amplifier AMP may beconnected to the j-th output line Vj through the j-th input terminalOTj, and a reference voltage VREF may be applied to a second inputterminal (e.g., an input terminal of a negative polarity (−)) of theamplifier AMP.

The capacitor CF may be connected between the first input terminal andoutput terminal of the amplifier AMP, and the switch SW may be connectedin parallel to the capacitor CF.

When the switch SW is turned off, the capacitor CF may integrate thecharge (e.g., a sensing signal) provided to the first input terminal ofthe amplifier AMP, and the amplifier AMP may output a sensing signalintegrated through the output terminal, in other words, the j-th outputsignal VOUTj.

When the switch SW is turned on, the capacitor CF may be initialized.

As described with reference to FIGS. 4 and 5 , the sensor pixel SPXLincludes the first and second transistors T1 and T2 connected betweensub-lines RX_S1 and RX_S2 of the j-th signal line RXj, and may reduce orblock both noise flowing through the j-th signal line RXj and noise (orleakage current) flowing from the optical sensor PSC by using the firstand second transistors T1 and T2. Therefore, sensing sensitivity of theinput sensing device ISD can be increased.

According to an exemplary embodiment of the present invention, as shownin FIGS. 4 and 5 , the input sensing device ISD includes a power linePL1; a driving line Hi; a first signal line RXj including sub-linesRX_S1 and RX_S2; a second signal line Vj connected to the sub-linesRX_S1 and RX_S2; and sensor pixels SPXL connected to the power line PL1,the driving line Hi, and the second signal line Vj, wherein at least onesensor pixel SPXL includes: an optical sensor PSC that transfers aphotoelectrically converted charge from the power line PL1 to a firstnode N1 in response to a driving signal provided through an i-th drivingline Hi of the driving lines Hi−1, Hi, and Hi+1; a first transistor T1connected between the first node N1 and a first sub-line RX_S1 among thesub-lines, wherein the first transistor T1 includes a gate electrodeconnected to the i-th driving line Hi; and a second transistor T2connected between the first node N1 and a second sub-line RX_S2 amongthe sub-lines, wherein the second transistor T2 includes a gateelectrode connected to the i-th driving line Hi.

FIG. 6 is a waveform diagram describing an operation of the sensor pixelof FIG. 5 , according to an exemplary embodiment of the presentinvention.

Referring to FIGS. 4 to 6 , the i-th driving signal SCANi may beprovided to the i-th driving line Hi, and the output signal Vout maycorrespond to the j-th output line Vj. In other words, the output signalVout may be a j-th output signal VOUTj output through an integralcircuit connected to the j-th output line Vj.

At a first time point t1, the i-th driving signal SCANi may be changedfrom a logic high level (or a gate-off voltage level) to a logic lowlevel (or a gate-on voltage level). At a second time point t2, the i-thdriving signal SCANi may be changed from the logic low level to thelogic high level.

In this case, the transmission transistor T_TX, the first transistor T1,and the second transistor T2 of the sensor pixel SPXL may be turned on,and the charge (or current) generated by the photodiode PD may betransferred to the j-th output line Vj through the transmissiontransistor T_TX, the first node N1, the first transistor T1, the secondtransistor T2, and the j-th signal line RXj (or first sub-line RX_S1 andsecond sub-line RX_S2).

The integral circuit described with reference to FIG. 4 may integratethe charge provided through the j-th output line Vj, and accordingly, avoltage level of the output signal Vout may be gradually increased andbe saturated at a specific voltage level.

When a reflected light corresponding to the valley is incident on thesensor pixel SPXL, the output signal Vout may change along a first curveWF1, and may have a first voltage level Vvalley. Alternatively, when areflected light corresponding to the ridge is incident on the sensorpixel SPXL, the output signal Vout may change along a second curve WF2,and may have a second voltage level Vridge. The second voltage levelVridge may be lower than the first voltage level Vvalley.

On the other hand, when noise flows into the input sensing device ISD(or sensor array PS), the output signal Vout corresponding to the ridgemay change along a third curve WF3 different from the second curve WF2,and may have a third voltage level Vnoise. In this case, a signal tonoise ratio may decrease (e.g., a value of “(Vvalley-Vridge)/Vnoise” maydecrease), and the ridge may not be sensed properly. For example, thedifference between the first voltage level Vvalley and the secondvoltage level Vridge may lessen due to the noise, thereby preventing theridge from being correctly sensed.

Therefore, the sensor pixel SPXL may reduce noise by using the first andsecond transistors T1 and T2 connected between the first and secondsub-lines RX_S1 and RX_S2 of the signal lines RXj−1, RXj, and RXj+1, andthus the sensing sensitivity (or a signal to noise ratio) of the inputsensing device ISD may be improved.

FIG. 7 is a drawing describing a change in noise caused by the sensorpixels in FIG. 5 .

Referring to FIGS. 4, 5 and 7 , when the sensor pixel SPXL does notinclude the first and second transistors T1 and T2, a load LOAD of thej-th signal line RXj may be expressed as 100%. For example, a level ofnoise NOISE flowing through the j-th signal line RXj having the loadLOAD of 100% may be about 8.5 mV.

The sensor pixel SPXL may be electrically blocked by at least one offirst and second transistors T1 and T2 in the first direction DR1 of thej-th signal line RXj, and thus, the level of the noise NOISE flowingthrough the j-th signal line RXj may be reduced. For example, the sensorpixel SPXL may be electrically blocked by the first transistor T1 or thesecond transistor T2 or by both of the first and second transistors T1and T2 at the same time.

As described with reference to FIGS. 4 and 5 , when each sensor pixelSPXL includes first and second transistors T1 and T2 and the j-th outputline Vj, the bad LOAD of the j-th signal line RXj may be reduced toabout 50% or less, and in this case, the level of noise NOISE flowingthrough the j-th signal line RXj may be reduced. For example, the levelof the noise NOISE may be reduced to about 5 mV or less.

FIG. 8 is a circuit diagram showing another exemplary embodiment of theinput sensing device of FIG. 3 .

Referring to FIGS. 3, 4, 5 and 8 , the input sensing device ISD_1 (orsensor array PS_1) of FIG. 8 is different from the input sensing deviceISD (or sensor array PS) of FIG. 4 in that at least one sensor pixelSPXL includes only one of the first and second transistors T1 and T2.

As shown in FIG. 8 , a first sensor pixel SPXL1 connected to the j-thoutput line Vj and farthest from the vertical driver 222, may includethe second transistor T2 described with reference to FIG. 5 and may notinclude the first transistor T1.

In addition, an n-th sensor pixel SPXLn connected to the j-th outputline Vj and closest to the vertical driver 222, may include the firsttransistor T1 described with reference to FIG. 5 and may not include thesecond transistor T2.

Any sensor pixel connected to the j-th output line Vj and disposedbetween the first sensor pixel SPXL1 and the n-th sensor pixel SPXLn mayinclude both first and second transistors T1 and T2 as described withreference to FIGS. 4 and 5 . In addition, any sensor pixel connected tothe j-th output line Vj and disposed between the first sensor pixelSPXL1 and the n-th sensor pixel SPXLn may include just one of the firstand second transistors T1 and T2 as described with reference to FIGS. 4and 5 .

As described with reference to FIG. 8 , the input sensing device ISD_1may include at least one sensor pixel (e.g., a first sensor pixel SPXL1and/or an n-th sensor pixel SPXLn) having a pixel structure differentfrom the sensor pixel SPXL described with reference to FIGS. 4 and 5 .

FIGS. 9A and 9B are circuit diagrams showing an exemplary embodiment ofa sensor array included in the input sensing device of FIG. 3 . In FIGS.9A and 9B, sensor pixels SPXLi−1, SPXLi, and SPXLi+1 included in thei−1-th to i+1-th sensor pixel rows and the j-th sensor pixel column areshown.

Referring to FIGS. 3, 4, 9A and 9B, a sensor array PS_2 shown in FIGS.9A and 9B is different from the sensor array PS shown in FIG. 4 in thatthe sensor pixels SPXLi−1, SPXLi, and SPXLi+1 include the firsttransistor T1 or the second transistor T2. For example, in FIG. 9A, eachof the sensor pixels SPXLi−1, SPXLi, and SPXLi+1 includes just onetransistor for controlling the connection between sub-lines RX_S1,RX_S2, RX_S3, and RX_S4 of the j-th signal line RXj.

The sensor array PS_2 may include a k-th sensor pixel group G_SPXLk(here k is a positive integer less than n), and the k-th sensor pixelgroup G_SPXLk may include sensor pixels SPXLi−1 and SPXLi, and a pair offirst and second transistors T1 and T2 included therein.

As shown in FIG. 9A, the k-th sensor pixel group G_SPXLk may include thei−1-th sensor pixel SPXLi−1 and the i-th sensor pixel SPXLi, in otherwords, two sensor pixels.

The i−1-th sensor pixel SPXLi−1 (or an odd numbered sensor pixel) mayinclude the i−1-th optical sensor PSCi−1 and the first transistor T1,and may not include the second transistor T2.

The i−1-th optical sensor PSCi−1 may be connected to the power line PL1,the i−1-th driving line Hi−1, and the second sub-line RX_S2. Since thei−1-th optical sensor PSCi−1 is substantially equivalent to the opticalsensor PSC described with reference to FIG. 5 except that it isconnected to the second sub-line RX_S2 instead of the first node N1,redundant descriptions will not be repeated. The first sub-line RX_S1,the second sub-line RX_S2, the third sub-line RX_S3, and the fourthsub-line RX_S4 may be included in the j-th signal line RXj.

The first transistor T1 of the i−1-th sensor pixel SPXLi−1 may include afirst electrode connected to the first sub-line RX_S1, a secondelectrode connected to the second sub-line RX_S2 (or a second electrodeof the transmission transistor T_TX in the i−1-th optical sensorPSCi−1), and a gate electrode connected to the i−1-th driving line Hi−1.

The i-th sensor pixel SPXLi (or an even numbered sensor pixel) mayinclude the i-th optical sensor PSCi and the second transistor T2, andmay not include the first transistor T1.

The i-th optical sensor PSCi may be connected to the powerline PL1, thei-th driving line Hi, and the second sub-line RX_S2. The i-th opticalsensor PSCi may be substantially equivalent to the i−1-th optical sensorPSCi−1. The i-th optical sensor PSCi (or the i-th sensor pixel SPXLi)and the i−1-th optical sensor PSCi−1 (or the i−1-th sensor pixelSPXLi−1) may be directly connected to each other through the secondsub-line RX_S2. In this case, a separate transistor for connecting ordisconnecting the i-th optical sensor PSCi and the i−1-th optical sensorPSCi−1 may not be disposed between the i-th optical sensor PSCi and thei−1-th optical sensor PSCi−1.

The second transistor T2 of the i-th sensor pixel SPXLi may include afirst electrode connected to the second sub-line RX_S2 (or secondelectrode of the transmission transistor T_TX in the i-th optical sensorPSCi), a second electrode connected to the third sub-line RX_S3, and agate electrode connected to the i-th driving line Hi.

The j-th output line Vj may be connected to the first sub-line RX_S1 andthe third sub-line RX_S3, and may be not directly connected to thesecond sub-line RX_S2 and the fourth sub-line RX_S4.

In other words, the first transistor T1 and the second transistor T2 forperforming the noise prevention function for the j-th signal line RXjmay be provided for each sensor pixel group (e.g., each sensor pixelgroup including two sensor pixels) instead of being provided for eachsensor pixel SPXL described with reference to FIG. 5 .

In this case, the number of transistors provided in the sensor arrayPS_2 (or input sensing device) may be reduced.

The i+1-th sensor pixel SPXLi+1 may be included in a different sensorpixel group from the k-th sensor pixel group G_SPXLk, and may includethe i−1-th optical sensor PSCi+1, and the first transistor T1 connectedbetween the third sub-line RX_S3 and the fourth sub-line RX_S4, similarto the i−1-th sensor pixel SPXLi−1.

As described with reference to FIG. 9A, the sensor pixel group (or eachof the sensor pixel groups) including a plurality of sensor pixels mayinclude a pair of first and second transistors T1 and T2. Therefore, thenumber of the first and second transistors T1 and T2 provided in thesensor array PS_2 may be reduced, and thus manufacturing cost may bereduced. Furthermore, an integration density of the sensor pixel may beincreased.

In FIG. 9A, the i−1-th sensor pixel SPXLi−1 (or i−1-th optical sensorPSCi−1) and the i-th sensor pixel SPXLi (or i-th optical sensor PSCi) inthe k-th sensor pixel group G_SPXLk is shown to be electricallyconnected through the second sub-line RX_S2, but the configuration ofthe k-th sensor pixel group G_SPXLk is not limited thereto. For example,as shown in FIG. 9B, the j-th signal line RXj may include only the firstsub-line RX_S1 and the third sub-line RX_S3 (e.g., odd numberedsub-lines), and may not include the second sub-line RX_S2 and the fourthsub-line RX_S4 (e.g., even numbered sub-lines, or sub-lines not directlyconnected to the j-th output line Vj). Thus, and the i−1-th sensor pixelSPXLi−1 and the i-th sensor pixel SPXLi in the k-th sensor pixel groupG_SPXLk may not be directly connected to each other.

FIG. 10 is a block diagram showing another exemplary embodiment of aninput sensing device included in the display device of FIG. 1A. An inputsensing device ISD_2 may include a sensor array PS_3 and an inputdetector 220.

Referring to FIGS. 1A, 3 and 10 , the input sensing device ISD_2 of FIG.10 is different from the input sensing device ISD of FIG. 3 in that itinclude a sensor array PS_3, a horizontal driver 221_1, and a groupdriving lines GH1 to GHp (here p is a positive integer less than n).Since the input sensing device ISD_2 of FIG. 10 is substantiallyequivalent or similar to the input sensing device ISD of FIG. 3 exceptfor the sensor array PS_3, the horizontal driver 221_1, and the groupdriving lines GH1 to GHp, redundant descriptions will not be repeated.

The sensor array PS_3 may include a sensor pixel group G_SPXL_1 (orsensor pixel groups), and the sensor pixel group G_SPXL_1 may include aplurality of sensor pixels SPXL1_1 to SPXLq_1 (here q is an integer of 2or more).

A specific configuration of sensor pixels SPXL1_1 to SPXLq_1 in thesensor pixel group G_SPXL_1 will be described later with reference toFIG. 11 .

The horizontal driver 221_1 may be connected to the sensor pixel groupG_SPXL_1 through the group driving lines GH1 to GHp (or second drivinglines). The horizontal driver 221_1 may be composed of a shift register,an address decoder, etc., and may sequentially apply the group drivingsignal (or group driving signals, or first driving signals) to the groupdriving lines GH1 to GHp. Here, the group driving signal may be a signalfor selectively driving the sensor pixel group G_SPXL_1. The sensorpixels SPXL1_1 to SPXLq_1 included in the sensor pixel group G_SPXL_1may receive the same group driving signal.

In addition, the horizontal driver 221_1 may be connected to the sensorpixels SPXL1_1 to SPXLq_1 through driving lines H1 to Hn (or firstdriving lines). The horizontal driver 221_1 may sequentially apply thedriving signal (or driving signals, or second driving signals) to thedriving lines H1 to Hn.

Each of the sensor pixels SPXL1_1 to SPXLq_1 selected by the groupdriving signal and the driving signal provided from the horizontaldriver 221_1 may sense light by using a photoelectric element therein,and may output an electrical signal corresponding to the sensed light.

FIG. 11 is a circuit diagram showing an exemplary embodiment of a sensorarray included in the input sensing device of FIG. 10 . In FIG. 11 ,sensor pixels SPXLi−1_1, SPXLi_1, and SPXLi+1_1 included in the k-thsensor pixel group G_SPXLk_1 (here k is a positive integer) and includedin the i−1-th to i+1-th sensor pixel rows and the j-th sensor pixelcolumn, are shown.

Referring to FIG. 11 , the k-th sensor pixel group G_SPXLk_1 may includean i−1-th sensor pixel SPXLi−1_1, an i-th sensor pixel SPXLi_1, and ani+1-th sensor pixel SPXLi+1_1. In other words, the k-th sensor pixelgroup G_SPXLk_1 may include three sensor pixels SPXLi−1_1, SPXLi_1, andSPXLi+1_1. However, this is just an example, and the number of sensorpixels included in the k-th sensor pixel group G_SPXLk_1 is not limitedthereto. For example, the number of sensor pixels included in the k-thsensor pixel group G_SPXLk_1 may be two, or four or more.

The i−1-th sensor pixel SPXLi−1_1 may include an i−1-th optical sensorPSCi−1 and a first transistor T1.

The i−1-th optical sensor PSCi−1 may be connected to the power line PL1,the i−1-th driving line Hi−1, and the second sub-line RX_S2_1, and maybe driven in response to a driving signal provided through the i−1-thdriving line Hi−1. Since the i−1-th optical sensor PSCi−1 issubstantially equivalent to the i−1-th optical sensor PSCi−1 describedwith reference to FIG. 9A, redundant descriptions will not be repeated.The first sub-line RX_S1_1, the second sub-line RX_S2_1, and the thirdsub-line RX_S3_1 may be included in the j-th signal line RXj.

A first transistor T1 of the i−1-th sensor pixel SPXLi−1_1 may include afirst electrode connected to the first sub-line RX_S1_1, a secondelectrode connected to the second sub-line RX_S2_1 (or a secondelectrode of the transmission transistor T_TX in the i−1-th opticalsensor PSCi−1), and a gate electrode connected to the k-th group drivingline GHk.

The i-th sensor pixel SPXLi_1 may include an i-th optical sensor PSCi,and may not include first and second transistors T1 and T2.

The i-th optical sensor PSCi may be connected to the power line PL1, thei-th driving line Hi, and the second sub-line RX_S2_1, and may be drivenin response to a driving signal provided through the i-th driving lineHi. The i-th optical sensor PSCi may be substantially equivalent to thei−1-th optical sensor PSCi−1. Since the i-th sensor pixel SPXLi_1 doesnot include the first and second transistors T1 and T2, the transmissiontransistor T_TX in the i-th optical sensor PSCi may be directlyconnected to the second sub-line RX_S2_1 and to transmission transistorT_TX of the i−1-th optical sensor PSCi−1 and the transmission transistorT_TX of the i+1-th optical sensor PSCi+1.

The i+1-th sensor pixel SPXLi+1_1 may include an i+1-th optical sensorPSCi+1 and the second transistor T2.

The i+1-th optical sensor PSCi+1 may be connected to the power line PL1,the i+1-th driving line Hi+1, and the second sub-line RX_S2_1, and maybe driven in response to a driving signal provided through the i+1-thdriving line Hi+1. The i+1-th optical sensor PSCi+1 may be substantiallyequivalent or similar to the i-th optical sensor PSCi described withreference to FIG. 9A.

In this case, the i−1-th optical sensor PSCi−1 (or the i−1-th sensorpixel SPXLi−1_1), the i-th optical sensor PSCi (or the i-th sensor pixelSPXLi_1), and the i+1-th optical sensor PSCi+1 (or the i+1-th sensorpixel SPXLi+1_1) may be directly connected to each other through thesecond sub-line RX_S2_1, and a separate transistor for connecting ordisconnecting them, may not be disposed among the i−1-th optical sensorPSCi−1, the i-th optical sensor PSCi, and the i+1-th optical sensorPSCi+1.

A second transistor T2 of the i+1-th sensor pixel SPXLi+1_1 may includea first electrode connected to the second sub-line RX_S2_1 (or a secondelectrode of the transmission transistor T_TX in the i+1-th opticalsensor PSCi+1), a second electrode connected to the third sub-lineRX_S3_1, and a gate electrode connected to the k-th group driving lineGHk.

The j-th output line Vj may be connected to the first sub-line RX_S1_1and the third sub-line RX_S3_1, and may not be directly connected to thesecond sub-line RX_S2_1.

In this case, the first transistor T1 and the second transistor T2 forperforming the noise prevention function for the j-th signal line RXjmay be provided for each sensor pixel group (e.g., a sensor pixel groupincluding three sensor pixels).

An operation of each of the k-th sensor pixel group G_SPXLk_1 and thei−1-th sensor pixel SPXLi−1_1, the i-th sensor pixel SPXLi_1, and thei+1-th sensor pixel SPXLi+1_1 included therein may be described withreference to FIG. 12 .

FIG. 12 is a waveform diagram describing an operation of the sensorarray of FIG. 11 , according to an exemplary embodiment of the presentinvention.

Referring to FIGS. 11 and 12 , a group driving signal GSCAN (or a firstdriving signal) may be provided to the k-th group driving line GHk (or afirst driving line), an i−1-th driving signal SCANi−1 (or, a seconddriving signal) may be provided to the i−1-th driving line Hi−1, an i-thdriving signal SCANi may be provided to the i-th driving line Hi, and ani+1-th driving signal SCANi+1 may be provided to the i+1-th driving lineHi+1.

In a first period P1, a second period P2, and a third period P3, thegroup driving signal GSCAN may have a logic low level (or a gate-onvoltage level). In a period other than the first to third period P1 toP3, the group driving signal GSCAN may have a logic high level (or agate-off voltage level).

When the group driving signal GSCAN of the logical high level isprovided to the k-th group driving line GHk (or when the group drivingsignal GSCAN is not provided to the k-th group driving line GHk), thefirst transistor T1 and the second transistor T2 in the k-th sensorpixel group G_SPXLk_1 may maintain a turn-off state, and mayelectrically separate the i−1-th sensor pixel SPXLi−1_1, the i-th sensorpixel SPXLi_1, and the i+1-th sensor pixel SPXLi+1_1 (and secondsub-line RX_S2_1) from the first sub-line RX_S1_1 and the third sub-lineRX_S3_1 (and the j-th output line Vj). In particular, the first sub-lineRX_S1_1, the second sub-line RX_S2_1, and the third sub-line RX_S3_1 maybe electrically separated from each other, and thus the possibility thatnoise flows through the j-th signal line RXj and a size of the noise maybe reduced.

When the group driving signal GSCAN of the logic low level is providedto the k-th group driving line GHk, the first transistor T1 and thesecond transistor T2 in the k-th sensor pixel group G_SPXLk_1 may beturned on, and may electrically connect the i−1-th sensor pixelSPXLi−1_1, the i-th sensor pixel SPXLi_1, and the i+1-th sensor pixelSPXLi+1_1 to the j-th output line Vj through the second sub-lineRX_S2_1. In this case, other sensor pixel groups (and sub-linescorresponding thereto) except for the k-th sensor pixel group G_SPXLk_1may maintain a state electrically separated from the j-th output lineVj.

In the first period P1 the i−1-th driving signal SCANi−1 may have alogic low level, and, as described with reference to FIG. 6 , aphotoelectrically converted charge (or a sensing signal) from the i−1-thsensor pixel SPXLi−1_1 (or the i−1-th optical sensor PSCi−1) may betransferred to the j-th output line Vj through the second sub-lineRX_S2_1, the first and second transistors T1 and T2, and the first andthird sub-lines RX_S1_1 and RX_S3_1.

Similarly, in the second period P2, after the first period P1, the i-thdriving signal SCANi may have a logic low level, and thephotoelectrically converted charge from the i-th sensor pixel SPXLi_1(or the i-th optical sensor PSCi) may be transferred to the j-th outputline Vj through the second sub-line RX_S2_1, the first and secondtransistors T1 and T2, and the first and third sub-lines RX_S1_1 andRX_S3_1.

In the third period P3, after the first and second periods P1 and P2,the i+1-th driving signal SCANi+1 may have a logic low level, and thephotoelectrically converted charge from the i+1-th sensor pixelSPXLi+1_1 (or the i+1-th optical sensor PSCi+1) may be transferred tothe j-th output line Vj.

As described with reference to FIGS. 11 and 12 , the sensor pixel groupincluding a plurality of sensor pixels may include a pair of first andsecond transistors T1 and T2. Therefore, the number of the first andsecond transistors T1 and T2 provided in the sensor array PS_3 may bereduced, and thus the manufacturing cost may be reduced, or theintegration density of the sensor pixel may be increased.

In addition, when the k-th sensor pixel group G_SPXLk_1 includes twosensor pixels, the i-th sensor pixel SPXLi_1 may be omitted in the k-thsensor pixel group G_SPXLk_1. In other words, the k-th sensor pixelgroup G_SPXLk_1 may include only two sensor pixels corresponding to thei−1-th sensor pixel SPXLi−1_1 and the i+1-th sensor pixel SPXLi+1_1.

Alternatively, when the k-th sensor pixel group G_SPXLk_1 includes fouror more sensor pixels, a plurality of i-th sensor pixels SPXLi_1 may beprovided in the k-th sensor pixel group G_SPXLk_1. In other words, thek-th sensor pixel group G_SPXLk_1 may include two or more sensor pixelssubstantially equivalent to the i-th sensor pixel SPXLi_1 between thei−1-th sensor pixel SPXLi−1_1 and the i+1-th sensor pixel SPXLi+1_1.

An input sensing device according to exemplary embodiments of thepresent invention and a display device including the same may reduce orblock noise and leakage current that flows through the first signal lineby including first and second transistors connected between sub-lines(or the first signal line) to which optical sensors are connected.Therefore, the sensing sensitivity of the input sensing device and thedisplay device including the same can be increased.

While the present invention has been described with reference toexemplary embodiments thereof, those skilled in the art will appreciatethat various changes in form and details may be made thereto withoutdeparting from the spirit and scope of the present invention as setforth in the following claims.

What is claimed is:
 1. An input sensing device, comprising: a powerline; driving lines; a first signal line including a first sub-line, asecond sub-line, and a third sub-line; a second signal line connected tothe first signal line; and sensor pixel groups connected to the powerline, the driving lines, and the first signal line, wherein at least onesensor pixel group among the sensor pixel groups includes: a firstoptical sensor for transferring a photoelectrically converted chargefrom the power line to the second sub-line in response to a drivingsignal provided through a first driving line among the driving lines; asecond optical sensor for transferring a photoelectrically convertedcharge from the power line to the second sub-line in response to adriving signal provided through a second driving line among the drivinglines; and a first transistor connected between the first sub-line andthe second sub-line, wherein the first transistor includes a gateelectrode connected to the first driving line.
 2. The input sensingdevice of claim 1, wherein the at least one sensor pixel group furtherincludes: a second transistor connected between the third sub-line andthe second sub-line, wherein the second transistor includes a gateelectrode connected to the second driving line.
 3. The input sensingdevice of claim 2, wherein the first, second and third sub-lines extendin a first direction and are arranged along the first direction, whereinthe second signal line is arranged parallel to the first signal line,and wherein the driving lines extend in a second direction crossing thefirst direction and are arranged along the first direction.
 4. The inputsensing device of claim 2, wherein each of the first and second opticalsensors includes: a photodiode connected between the power line and thesecond sub-line; and a transmission transistor connected between thephotodiode and the second sub-line, wherein the transmission transistorincludes a gate electrode connected to a corresponding driving lineamong the driving lines.
 5. The input sensing device of claim 4, whereinthe second signal line is directly connected to each of the firstsub-line and the third sub-line, and is not directly connected to thesecond sub-line.
 6. The input sensing device of claim 2, wherein the atleast one sensor pixel group further includes a third optical sensor,wherein each of the first, second and third optical sensors includes: aphotodiode connected between the power line and the second sub-line; anda transmission transistor connected between the photodiode and thesecond sub-line, wherein the transmission transistor includes a gateelectrode connected to a corresponding driving line among the drivinglines.
 7. The input sensing device of claim 6, wherein the seconddriving line is the same as the first driving line, and wherein thesecond driving line is different from the driving line connected to thegate electrode of the transmission transistor in each of the first,second and third optical sensors.
 8. The input sensing device of claim7, wherein, during application of a first driving signal having agate-on voltage level to the first driving line, a second driving signalhaving a gate-on voltage level is sequentially provided to the first,second and third optical sensors.
 9. The input sensing device of claim1, wherein a width of the second signal line is greater than a width ofthe first signal line.